DAVIS--Research entomologist Yigen Chen of the UC Davis Department of Entomology and Nematology will open the department's fall seminar series with a presentation on Wednesday, Oct. 1 on "Interactions Between Two Invasive Wood-Boring Insects with Their Respective Host Plants."

Chen, an associate project scientist, will discuss the emerald ash borer and the goldspotted oak borer and their interactions with their host plants. His talk is from 12:10 to 1 p.m. in 122 Briggs Hall.

Research entomologist Steve Seybold of the USDA's Forest Service and an affiliate of the Department of Entomology and Nematology is the host.

Chen, who holds a master's degree in applied statistics (2010) from Michigan State University, obtained his doctorate in entomology from the University of Georgia in 2007. For his dissertation research, he investigated various effects of nitrogen fertilization on tritrophic interactions among cotton plants, the beet armyworm, Spodoptera exigua, and the parasitoid, Cotesia marginiventris. The project integrated ecological, chemical, nutritional, and behavioral elements to evaluate the role of nitrogen in shaping tri-trophic interactions in cotton.

Chen carried out postdoctoral research at Michigan State University's Department of Entomology from 2008 to 2011 on the behavioral, chemical, and nutritional interactions between the invasive emerald ash borer, Agrilus planipennis, and ash trees. He relocated to UC Davis in July 2011 to lead an effort to improve trapping lures for detection of another invasive pest, the goldspotted oak borer, Agrilus auroguttatus.

In collaboration with research entomologists from the USDA Forest Service, Chen is now working to develop management options for the invasive walnut twig beetle, Pityophthorus juglandis, and polyphagous shot hole borer, Euwallacea sp.

Chen's overarching research goals are to build arthropod pest management systems that emphasize naturally occurring pest suppression agents and environmentally friendly tactics, that is, insect sex pheromones and other semiochemicals, in a holistic, ecosystem-based approach. He is also interested in studying pest population dynamics in the context of various pest management tactics, agronomic practices, and abiotic environmental factors (e.g., temperature and precipitation) with mathematical and statistical tools.

Wednesday, Oct. 29Clifford OhmartEntomologist and vice president of professional servicesSureHarvest, sustainable agricultureTitle: "Sustainable Agriculture: What Is Happening Out on the Farm?"Host: Michael Parrella, professor and chair of the Department of Entomology and Nematology